Filter and valve mechanism



Now-28, 1950 R. Q. BOYER FILTER AND VALVE MECHANISM 3 Sheets-Sheet l //M/M/M////// Filed Nov. 30, 1944 IN VEN TOR. ,@Oer/Qoyef" Nov. 28, 1950 y R, Q. BOYER 2,531,802

FILTER AND VALVE MECHANISM Nov. 28, 1950 R. Q. BOYER FILTER AND VALVE MECHANISM 5 Sheets-Sheet 3 Filed Nov. 30, 1944 Patented Nov. 28, 1950 :,ssisoz r11/rsa AND vALvE MacnmsM Robert Q. Boyer, Berkeley, Calif., assigner to the United States o! Amerie United States Atomic a as represented by the Energy Commission Application November 30, 1944, Serial No. 566,002

(Cl. 21o-150) 16 Claims.

This invention relates to valve mechanisms and more particularly to a combination of valve and filter apparatus designed to handle extremely valuable precipitates substantially without loss.

In the copending application of Ross Cummings, Serial No, 571,421, filed January 5, 1945, there is described a process and apparatus for filtering a slurry to form a filter cake, washing the cake, drying the cake by means of a suitable volatile drying liquid, and removing the cake from the cake-forming filter which are particularly adapted for use with precipitates of extremely valuable material by reason of the substantial avoidance of any possible loss of precipitate in the process.

The present invention relates to the process disclosed in said copending application, and more particularly to an improvement in said process and apparatus wherein contamination of the slurry, wash liquor, or drying agent is substantially avoided by means of an improved valve mechanism associated with the apparatus.

The present invention includes, as an important part thereof, an improved valve mechanism for selectively opening any one of a plurality of lines while assuring complete closure of the remainder of the lines.

It is accordingly one object of this invention to provide an improved apparatus for filtering. washing, drying, and recovering precipitate which prevents contamination of the associated" slurry, wash liquor, and drying liquid.

It is a further object of this invention to provide apparatus for carrying out such filtering, washing, drying, and recovering process which is particularly adapted for use with precipitates of extremely valuable material.

It is a further object of this invention to provide a valve mechanism for selectively opening to a single conduit any one of the slurry, wash liquor, or drying liquid withdrawal lines of the combined apparatus disclosed, while positively preventing leakage to or from the otherl of such lines.

It is a further object of this invention to provide a valve mechanism of the type described which can be mounted either on a control panel, in the filter column or otherwise in the system, as desired.

It is a further object of this invention to provide a valve mechanism foi` use in the processes having a fluid pressure differential in the lines to be controlled in which the reduced pressure on one side of the valve aids in maintainingsecure closure of the valves.

It is another object of this invention to provide a valve mechanism of the type described especially adapted for use in the filter process disclosed and which is simple and economical to construct and easy to operate.

In general, the filter process of this invention involvesthe use of a series of tanks in a horizontal alignment and respectively containing a slurry to be filtered, a wash liquor, a suitable drying fluid, and a filter cake-receiving chamber. Each of the tanks in order is adapted to receive one or more thimble lters, which are employed to pick up the precipitate from the slurry in the first tank and to carry the resulting filter cake to the succeeding tanks in sequence for washing and drying the filter cake and removing itfrom the filter. The thimble filters are manipulated in accordance with this series of operations by means of apparatus adapted to support each thimble filter independently as more completely disclosed in the above-mentioned copending application of Ross Cummings. The apparatus includes a iiltering column having a thimble filter attached to the lower end thereof. The filter column includes a filter head for holding the thimble filter, a lower tubular assembly for supporting the filter head, a suction-controlled valve unit supporting the lower tube assembly and an upper tubular assembly supporting a valve unit and housing a plurality of suction tubes selectively operable by the valve unit to apply suction to the thimble filter. Each filtering column is supported for independent horizontal movement along the vline of the several tanks and for vertical movement over each of the tanks to lower the associated thimble filter into and out of each tank in order.

In the accompanying drawings:

Figure 1 is an elevation, partly in section, of a preferred embodiment showingthe valve, tank, and filter mechanism of this invention.

Figure 2 is an enlarged fragmentary vertical section showing the vacuum seal employed in the filter column.

Figure 3 is an enlarged elevation, partly broken away and in section, of the valve mechanism shown in Figure l.

Figure 4 is a section on the line I-t of Figure 3.

Figure 5 is a section on the line 5-5 of Figure 4.

Figure 6 is a fragmentary elevation of an alternative embodiment of this invention showing the valve mechanism installed upon a panel.

Figure 7 is an enlarged vertical section of the valve mechanism shown in Figure 6.

Figure 8 is a section on the line 8-8 of Figure 7.

Referring more particularly to the drawings in the embodiment illustrated in Figures l to 5 there is illustrated a precipitate-recovery apparatus including a receptacle generally designated I made of any suitable non-porous material chemically resistant to the solutions to be contained therein. divided by partitions 2, 3 and 4 into four 3 tanks or compartments 6, 8, 1, and 8. Tanks 5, 6, and 1 are adapted to contain a slurry to be filtered, a suitable wash solution, and a suitable volatile anhydrous organic solvent, respectively. Tank 8 is adapted for housing the thimble filter during the scraping operation as hereinafter more particularly described. The bottoms of each of the tanks 5, 6, and 1 are sloped toward outlet openings to which are connected outlet pipes l2 which may be provided with suitable valves (not shown). Each of the tanks 5, 6, and 1 is also provided with an opening I3 communicating with a pipe, not shown, for supplying to that tank the slurry, the wash solution, or the organic solvent to be contained therein. The tank 8 is provided with an outlet 8 through which the material removed in the scraping operation may fall into any suitable container (not shown).

The tank I and its associated apparatus delscribed above is adapted to accommodate one or more thimble filters 34. The thimble 34 may be formed of any suitable material. In the accompanying drawings there is illustrated a single thimble lter 34. However, if desired a plurality of such thimble iilters may be employed. The thimble filter 34 is adapted to be dipped into the tank containing the slurry to be filtered and to have suction applied to the inside of the thimble to draw filtrate through the porous walls and to cause a lter cake to build up on the outside of the thimble. The thimble filter is then adapted to be lifted vertically out of the tank 5, moved horizontally over the tank 6, and lowered vertically into the wash solution in the tank 6. In this Position suction is again applied to the inside of the/thimble toy draw Wash solution through the filter cake tothe inside of the thimble, thus displacing residual filtrate held by the filtrate cake. The thimble filter is then raised vertically out of the tank 6, moved horizontally to a position above the tank 1 and lowered into a suitable volatile organic solvent contained in the tank 1. Suction is again applied to the inside ofthe thimble to draw the organic solvent through the vfilter cake into the inside of the thimble, displacing residual wash solution held by the iilter cake. The thimble filter is then again raised vertically out of the tank 1 with suction still applied to the inside of the thimbles, whereby air is drawn through the iilter cake, causing the volatile solvent to evaporate, thus leaving the filter cake in a dry condition. The thimble illter is next moved horizontally to the position indicated generally, in broken lines, at I8 in Figure 1 and then lowered into tank 8.4 The thimble lter 34 carries a plurality o1 scraper blades 35' mounted thereon adapted to be rotated by means of the handle 36 securely aiilxed to the scraper hub 31. scraper blades 35 through approximately a quarter of a turn, the filter cake is removed from the thimble and falls into the tank 8, through the outlet opening 9 and into any suitable collector, not shown.

The lter column illustrated in Figures l to 4 By rotating the includes as principal elements the thimble iilter 34, the scraper blades 35, a filter head 38 supporting the thimble filter, a selective valve unit indicated generally as 39, an upper tubular assembly 40 supporting the valve unit, and a bracket- 4| supporting the entire iilter column. The iilter thus described is adapted for use with the rail mechanism for controlling horizontal movement and also for a vertical movement into and out of the tanks 5, 8, 1, and 8 as more fully described in the aforementioned copending application.

As shown in Figures 1 and 2, the iilterhead 38 is threadedly connected to a fitting 42 onto which the upper rim of the thimble iilter 34 may be iitted and cemented, by the use of a suitable ceramic cement 26. The fitting 42 has an inwardly extending portion 21 apertured at 28 for the passage of the tube |01. The portion 21 is bored out for a portion of its length and internally threaded for the reception of a packing gland 30. A packing member 29 is retained in the bore by the gland 30.

The scraper blades 35 are ilxedly connected by any suitable means such as the set screws 44 to the scraper hub 31 and a compression spring '43 having its lower end abutting upon the fitting 42 is positioned about the lter head 38 and retained under a slight compression by the shoulder 31a within the scraper hub 31. For scraping the lilter cake from the filter. a handle 36 securely aiiixed to the ring 31 is provided for rotation of the blades 35 which are urged into intimate contact with the outer surface of the thimble filter 34 by the compression spring 43.

As best shown in Figure 4, a nipple 45, internally threaded as at 46 for connection with the external threads 41 on the upper end of the filter head 38 and having viewing apertures or windows 48 is positioned in the filter column and permits the operator to detect visually the presence of any solid mater in the line |06.

The nipple 45 is externally threaded as at 48 for threaded connection with internal threads 5D of valve head 5|. The valve head 5| has a central aperture 5|a and forms the lower member of the valve unit 39. The valve unit 39 comprises a four-way pinch valve adapted to open selectively one only of four associated tubes. Positioned above the valve head 5| and threadediy connected thereto by external threads 52 mating with internal threads 53 is a cylinder 54. The cylinder 54 is closed at its upper end by an end wall 55 having a central aperture 56 and four radially disposed apertures 51 symmetrically arranged near its periphery.

A mandrel 58 is provided having a lower disklike portion 59an intermediate block 60 having a regular polygonal, horizontal cross-section, shown here in the shape of a square, and an upper disk member 6| having a reduced portion 62 forming a shoulder 83. The reduced portion 62 is externally threaded as at 64.

The mandrel 58 has a central aperture or bore 65 registering with the aperture 56 in the end wall 55 and a bolt 66 is positioned in these apertures and removably secured by a nut 81, thus removably attaching the end wall 55 to the mandrei.

The disk member 59 and the disk member 8| have four radially disposed apertures 2| and 22, lrespectively, registering with the apertures 51 in the end wall 55 and having their axes parallel to and spaced slightly from the fiat side walls of the block 60.

As shown in Figure 3, a series of four pivot pins 68 is mounted between the disk 8| and the disk 59 in the space opposite the flat sides o! the block 68. These pins 68 are provided with heads 68 counter-sunk in the disk 59 and threaded into internal threads in the disk 6|. The pins 68 also carry a pair of spacers 18. As more clearly illustrated in Figure 5 the` pins 68 are positioned adjacent the four corners of the block and slightly spaced away from the fiat sides thereof. Each ot the pins 88 carries an associated pinch lever 1| for a purpose hereinafter described.

Disposed above the mandrel 58 and threadedlv connected thereto by the internal threads 12 mating with the external threads 84 is an irregular collar member 13 having a reduced portion 14, the bore of which is enlarged for a portion only of its length to form an internal shoulder 15.

A gasket 18 is disposed immediately above the collar 13 and a washer 11 having a gasket-retaining shoulder 18 is provided in engagement with the gasket 18.

A valve operating sleeve 19 is disposed about the washer 11, collar 13, mandrel 58, and upper end wall 55 of cylinder 54 as shown. The sleeve 18 has an inwardly turned shoulder 80 engaging the upper surface of the washer 11 and may be provided with a flange 8|, having a knurled surface 8l-a.

As clearly illustrated in Figure 5, the sleeve 19 has an arcuate slot 82 communicating with the space formed by the mandrel 58 and positioned in the same plane as the pinch levers 1| The sleeve 19 is mounted for rotation on the washer 11.

The upper tubular assembly 40 supporting the valve unit includes a tubular housing 83, the

lower end of which abuts upon and is secured to, as by welding or by any other suitable means, the shoulder 15 of the collar 13. ring 84, having a plurality of set screws 85, is mounted upon the housing 83 and with the set screws 85 firmly set, serves to retain the sleeve 19 in position upon the valve unit.

Referring now to Figure l, the tubular housing 83 is shown to carry a rib 85 of rectangular cross-section running longitudinally of the housing 83 and is secured thereto by counter-sunk screws 81 threaded into a backing strip 88 positioned parallel to the rib 86 and within the heus ing 83.

The bracket 4| is formed of a split collar 89 having flanges 80 bolted together by bolts 9| to clamp the collar to the housing 83. Both time rib 86 and the collar 89 adapt the column for use in the-type of supporting and translating mechanism shown in detail in the above-mentioned copending application.

Four tubes numbered 92, 83, 94, and 95, respectively, are housed within the house 83. These tubes are preferably of rubber or other flexible material chemically resistant to the materials employed in the filter process. Just above the lower end of the housing 83, Figure 4, there are shown lengths of glass or other tubing material 98, 91. and 98 connected to each of the rubber tubes 92, 95, and 94, respectively. A similar length of tubing (not shown) is connected to the rubber tube 93. These lengths of tubing are provided in order -to permit disconnection of 'the housing 83 from the valve unit without necessitating removal of the tubes contained within the valve unit itself. Below the lengths of tubing just described are connected lengths of rubber or other resilient tubing 99, |00, |0|, and |02 which pass adjacent the flat sides of the block 60 of the mandrel 58, through the holes 2| and 22 in the disks 59 and 8|, respectively; and through the apertures 51 in the end wall 55 of the cylinder 54. Y

A manifold |03 having a port for each of the tubes 99, |00, lili, and |02 on one side thereof and a single port |04 on the other side thereof is attached to the tubes as shown. By means of a short length |05 of rubber or other flexible A retaining :A

tubing, a section of glass or otherwise transparent tubing I 08 is attached to the port |04. The length |08 of transparent tubing passes through the central aperture 5 I a in the valve unit 5| and is thus positioned in a manner to be viewed through the windowsl 48. Below the windows 48 a tube |01 of stainless steel or other suitable material is attached to the transparent tube |08 by means of another short length of flexible tubing |08. The tube |01 terminates adjacent the bottom of the thimble filter 34.

The valve unit `38 is adapted to open selectively any one of the lines 88, |00, |0i, or |02 while keeping the others securely closed. It suffices simply to rotate the sleeve 19 in a counterclockwise direction (as viewed in Figure 5), thus causing' the pinch lever 1|a,by engagement with the inner surface of the sleeve 19, to assume a position parallel to the straight side of the block 80. In this position, the tube 99 will be flattened and securely closed, while, by virtue of the movement of `the arcuate slot 82 into a position freeing the pinch lever 1| b, that lever will spring outward under the force of the resilient tube |00, thus opening that tube. Further counter-clockwise rotation of the sleeve 19 will close the lever 1lb and open the lever 1|c, while still further rotation will close the lever 1|c and open the next pinch lever.

While there is illustrated an arrangement employing a block having a square cross-section and four tubes 99, |00, |0i, and |02 are shown, it will be apparent that a block 80 having a crosssection in the shape of any form of a regular polygon may be used and any number oi associated tubes may be employed, as desired. For example, a cross-section in the shape of an equilateral pentagon may be employed and, consequently, five flexible tubes or a hexagon may be employed with six tubes.

The pinch levers 1| are especially effective in achieving a secure closure of the associated tubes, inasmuch as the filter process employs suction means (not shown) connected to the tubes and the reduced pressure on the upper side of the filter column tends to assist in drawing together the walls of the tubes and thus to assure a tight closure.

In Figures 6, '1, and 8 there is shown an alternative embodiment of this invention employing a similar thimble filter 34', shown positioned in the tank 5. The tube |01 carries a sleeve I 09 having a suitable manipulating lever I0 attached thereto. A length of flexible tube is connected to the tube |01'. The valve unit 39' is shmvn mounted upon a panel H2.

The valve unit 39 includes a mandrel 58', generally similar to the mandrel 58 above described and formed of a disk a central block 60' having a square cross-section, and a disk member 8 I' having a reduced portion ||3 forming a shoulder i4. The mandrel 58 is provided with a centrai aperture 55'.

Four pivot pins 68 similar to the pins 88 support :izour pinch levers 1| in the same manner as above described. fi. sleeve member 19' having an inwardly turned flange ||5 surrounds the mandrel 58, the flange ||5 engaging the shoulder H4.` An arcuate slot 82' is formed ,in the sleeve 18'. The disk 6|' is provided with four equallyspaced holes 22 registering with similar holes 2|' in the disk 59'. Four outwardly extending spokes ||8 are provided, welded as at ||1 to the sleeve 19 and a hub ||8 is secured, as by screws H9, to the spokes H8. The hub ||8 extends inwardly beyond the outer edge of the connecting with the tubes 99', |00', |0|', and j |02'. These tubes pass directly fromthe marilfold through the holes 2|' in the disk 59', then closely adjacent the flat sides of theV block 60' and thence outwardly through the holes 22' in the disk 6|' as shown.

In both embodiments of the innvention illustrated, the tubes 92, 93, 94, and 95 in the first embodiment and the tubes 99', |00', |0|', and

|02' in the second embodiment may be connected to appropriately associated pumps (not shown); whereby suction may be applied to these lines, and the pumps may lead in turn to appropriate receptacles (not shown) for the slurry, wash liquor, and drying fduid.

The operation of the above described lter column is as follows: The tank 5 having been filled, through the opening i3, with a slurry to be filtered one or more filter columns are lowered into the tank until the thimble filter 34 is substantially submerged. The sleeve 19 (19 in Figures 6 to 8) is then rotated until one of the levers, e. g., 1|a, is free, thus opening the tube 99. Suction is applied to the tube 92 and communicated by the tube 99 and the manifold |03 to the tube |01 causing a filter cake to biuld up upon the outer surface of the thimble filter 34. The lter column is then raised out of the tank 5 and transferred to the tank B which has meanwhile received a charge of wash liquor. The sleeve 19 is meanwhile rotated sufiiciently to close pinch lever 1|a and tube 99 and open pinch lever 1|b and tube |00.

In some cases, it may be desired to reslurry the filter cake in the tank 6 in which case the tube 93 communicating with the tube |00 may be attached to a source of air pressure which may be used to blow off the filter cakeand to agitate the wash liquor, thus completely reslurrying the f precipitate. The sleeve 19 may then be given another slight turn sufficient to close the pinch lever 1lb and the tube |00 and to open 'the pinch lever 1|'c and the tube |0|. The tube |0I, through tube 94, is also attached to a suitable suction pump, thus again building up on the filter 34 a filter cake and simultaneouslywashiug the cake free of any entrained filtrate. l Obviously, however, the reslurrying step sometimes may be omitted, in which case the tube |00 and the connected tube 93 may also be connected with a suction pump to merely wash the cake, rather than a vsource of air pressure, for reslurrying.

When the filter cake is again built up, and when it has been sufficiently washed in the tank 6 the lter column is raised out of the tank 6 and transferred to the tank 1. Tank 1 has, meanwhile, received a charge of an organic anhydrous volatile drying liquid. The sleeve 19 is again rotated suiliciently to close pinch lever 'I Ic and the tube |0| and to `open the next pinch lever and the tube |02. Tube |02 through tube 95 is also connected with a suction pump. thus drawing the drying liquid through the filter cake. Next the filter column is raised out of the tank 1 and the tubes I 02 and 95 are left open. Due to the volatile nature of the drying liquid all of the liquid is drawn off in vapor form from the filter cake which is thus completely dried. The filter column is then transferred to the tank 9, the scraper blades 35 are rotated by means of the handle 39, and the filter cake scraped from the filter 34. The removed filter cake falls into the tank 9- and discharges through outlet 9 to its collector.

During the above described steps, the operator may at all times observe the various liquids in the tube |06 through the windows 48 and thus check them for clarity to determine whether or not the filter process is functioning correctly.

The carrying out of the filter process using the embodiment illustrated in Figures 6, 7, and 8 is essentially the same, differing only in the fact that the valve unit 39 is located at a central panel ||2, which is desirable in the cases where a plurality of units are-operated as a bank.

As more fully set forth in the above mentioned copending application of Ross Cummings, the general arrangement of filter column set forth is particularly advantageous for the handling of extremely valuable precipitates. Inasmuch as the entire process is carried out within the limits of the receptacle I and as all of the filtrates, wash liquors, and drying liquids may be recovered and recycled, loss of precipitate is absolutely minimized. Furthermore, the pinch valve structure of the present invention positively prevents any contamination of .the various liquids by leakage back down the tube |01. It will be appreciated, however, that while the valve structure disclosed is particularly useful in the filter process described, obviously it is of general utility and may be employed to advantage in any case where it is desired to open selectively one only of a plurality of such lines.

While there has been described what are atV present considered preferred embodiments of the invention, it will be understood that various modifications may be made therein. It is intended to cover in the appended claims, therefore, all such modifications a's fall within the true scope and spirit of the invention and the invention accordingly is not to be considered as limited to the exact details shown, except as it may be so defined in the following claims.

What is claimed is:

1. A multiple port valve comprising a central body member, a plurality of flexible tubes carried by said member, a sleeve element surrounding said member and mounted for movement with respect thereto, and pinch mechanism carried by said member and engageable by said element for simultaneously releasably pinching a plurality of said tubes into closed position against said body member while leaving one tube open, said lpinch mechanism comprising a plurality of spaced pinch members, each pinch member being adapted to cooperate with a single tube, and said sleeve element having means for releasing said pinch members from pinching relation with said tubes seriatim and one at a time.

2. A multiple port valve as recited in claim l, wherein said pinch mechanism comprises a plurality of pivoted pinch levers, the free end of each lever extending into the path of movement of said movable sleeve element.

3. A multiple port valve as recited in claim 1, wherein said sleeve element is rotatable about said central body member.

4. A multiple port valve as recited in claim i.

wherein said sleeve element is rotatable about said central body member and is provided with an aperture through which a selected portion of the pinch mechanism isadapted to project. l

5. A multiple port valve comprising a central anvil member, a plurality of iiexible tubes passing adjacent said anvil member, a movable sleeve member surrounding said anvil member and tubes and having an aperture therein, a plurality o! pinch levers respectively mounted adjacent each of said tubes and extending into the path of movement oi' the aperture in said sleeve member, and each lever serving in one position to pinch its associated tube against said anvil member to close said tube, said sleeve member serving to retain all but one of said pinch levers releasably in said position while permitting one of said levers to open through said aperture and being rotatable to permit selective opening of individual tubes.

6. A multiple port valve as recited in claim 5, wherein said levers are pivotally mounted on said anvil member as a fulcrum adjacent their inner ends.

7. A multiple port valve as recited in claim 5, wherein said anvil member comprises a regular polygonal cross section and said iiexible tubes are disposed respectively adjacent a iiat side of said anvil member.

8. A valve mechanism comprising a centrally disposed element, a plurality of levers disposed about said element and pivotally mounted thereon, a corresponding plurality of iiexible conduits disposed about said element and respectively positioned between said levers and said element, each one of said levers being movable about its pivot toward said element to deform from its normal conguration the corresponding one of said flexible conduits in order to decrease the eilective opening therethrough and movable about its pivot away from said element to permit said one exible conduit to resume its normal configuration in order to increase the effective opening therethrough, and lever-actuating means surrounding said element and conduits and including a collar rotatably mounted on said element for selecting any one of said levers to permit its movement away from said element while retaining the remainder of said levers in maximum tube deforming position, said collar contacting the outer ends of said levers in said conduits deforming position thereof.

9. Filtering apparatus comprising hollow, porous lter element open at one end, a nonporous closure therefor, a multiple port valve unit having a central anvil member, a first conduit passing through said closure mfmmmiieating at one end with the interior of said hol low filter element and at its opposite end wi` port of said valve unit, a plurality of addi ,al conduits each communicating with one of a con responding number of additional ports of said valve unit, ilexible portions positioned adjacent said anvil member, a pluraliin of pinch levers respectively associated with said exible portions, each of said pinch levers being adapted in closed position to pinch its associated ilexible portion against said anvil member, and a movable sleeve member surrounding said anvil member and flexible portions oi' the conduits adjacent thereto and contacting one end of said pinch levers, said sleeve member and levers actuated thereby being operable selectively to place said additional conduits indisaid additional conduits each having l0 vidually into communication with said. first conduit.

10. Apparatus as recited in claim 9, wherein said movable sleeve member is provided with an aperture into which a selected one of said pinch levers projects while the ilexibie conduit associated with the selected pinch lever remains in communication with said first conduit.

11. Apparatus as recited in claim 9, wherein each o1' said additional conduits is connected to an exhaust means.

12./A lter column comprising a thimble iliter, an exhaust tube within said thimble filter, a tubular housing member supporting said illter, a manifold connected with said exhaust tube, a plurality of ilexible tubes mounted within said tubular housing member and communicating with said manifold, a selective valve connected to said tubular housing and having an anvil member, a plurality of pinch levers, and a movable apertured sleeve member surrounding said anvil member and adapted to selectively force all but one of said pinch levers against all but one of said flexible tubes to pinch said tubes against said anvil member and close said tubes, and exhaust means connected to said flexible tubes whereby material exhausted through said filter is passed to a selected flexible tube.

13. A illter column comprising a thimble filter, an exhaust tube within said thimble filter, a tubular housing member supporting said lter, a manifold connected with said exhaust tube. a plurality oi' flexible tubes mounted within said tubular housing member and communicating with said manifold and a selective valve connected to said housing member and having an anvil member, a plurality of pinch levers andi a movable, apertured sleeve member surrounding said anvil member and adapted selectively to force all but one of said pinch levers against said all but one o1' exible tubes to pinch said tubes against said anvil member and close said tubes, and ex-l haust means connected to said ilexible tubes whereby material exhausted through said filter is passed to a selected ilexible tube, and said sleeve member being mounted on said anvil member for rotation to selected.

14. Filtering apparatus comprising atubular member, al ltering element carried on the lower end of saidttubular member, a centrally disposed element carried by the tubular member intermediate its ends, a plurality of levers disposed about said element and pivotally mounted thereon, a corresponding plurality of conduits carried by said tubular member and having flexible portions disposed about said element and communieating with the interior of the filtering element, the exible portions being respectively positioned between said levers and said element, each one of said levers being movable about its pivot toward said element to deform from its normal configuration the corresponding one of said ilexible portions in order to decrease the effective opening therethrough and movable about its pivot away from said element to permit said one flexible portion to resume its normal conilguration in order to increase the etlective opening therethrough, and lever-actuating means surrounding said centrally disposed element and conduits and including a collar rotatably mounted on said tubular member i'or selecting any one of said levers to permit its movement away from said element while retaining the remainder of said levers in maximum tube dechange the ilexible tube so l1 forming position, said collar contacting the outer ends of said levers in said tube deforming position thereof.

15. Filtering' apparatus comprising a hollow, porous illter element open at one end, a nonporous closure therefor, a conduit passing through said closure and communicating at one end with the interior of said hollow illter element and having its opposite end leading to a remote control panel, a plurality of flexible tubes located in said panel, a manifold connecting each of said tubes to said conduit, an anvil member, a corresponding plurality of pinch levers associated with said tubes, each of said pinch levers being adapted in closed position to pinch its associated tube against said anvil member, and lever-actuating means surrounding said anvil member and tubes and movable relative to said anvil member to permit selective opening of one of said pinch levers while retaining the remainder of said pinch levers in closed position, said leveractuating means contacting the outer ends of each lever in the closed position o! said levers. 16. Filtering apparatus comprising a hollow, porous nlter element open at one end, a nonporous closure therefor, a conduit passing through said closure and communicating at one end with the interior of said hollow lter element and having its opposite end leading to a remote control panel, a. plurality of flexible tubes lo cated in said panel, a manifold connecting each of said tubes to said conduit. an anvil member, a corresponding plurality of pinch levers associated with said tubes, each of said pinch levers being adapted in closed position to pinch its associated tube against said anvil member, leveractuating me'ans surrounding said anvil member and tubes and movable relative to said anvil member to permit selective opening of one of said pinch levers while retaining the remainder of said pinch levers in closed position, said leveractuating means contacting the outer end of each lever in the closed position of said levers, and exhaust means connected to said flexible tubes whereby material exhausted through said illter is passed to a selected flexible tube.

ROBERT Q. BOYER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number 

